Conventionally, electronic dictionary devices (hereinafter, simply referred to as “electronic dictionaries”) are known that are built with databases (dictionary DBs) of various dictionaries, such as a Japanese language dictionary, a Japanese-English dictionary, and an English-English dictionary. The dictionary DB collects information on a headword associated with explanatory information (e.g., character data, image data, motion-image data, and sound data) for explaining and illustrating the headword, and systematically organizes such information so that a computer can search such information.
The electronic dictionaries have various functions in order to enhance the user-friendliness of searching. In particular, according to electronic dictionaries built with DBs of a plurality of dictionaries, devising is done to enhance the usability such as making the selection of the dictionary by a user unnecessary by searching the plurality of dictionaries simultaneously.
For example, Unexamined Japanese Patent Application KOKAI Publication No. 2006-106889 discloses a technology of giving a preference depending on the level of a user to each dictionary in an electronic dictionary provided with a plurality of dictionary information, and of displaying a list of search results in the order of the preference. According to this technology, it becomes possible to provide an electronic dictionary with good user-friendliness that can preferentially present a search result from a dictionary depending on the level of the user (e.g., junior high school/high school/college).
According to the conventional technology disclosed in Unexamined Japanese Patent Application KOKAI Publication No. 2006-106889, however, even if searching is performed in a plurality of document groups (dictionaries), search results are not output from all over the document groups, and may be output from some document groups in an unbalanced manner. Hence, search results from the plurality of document groups are not effectively presented to the user.
This will be explained in more detail with an example electronic dictionary device built with a plurality of dictionary DBs. When searching is performed with a Japanese search string, Japanese search string is contained many times in explanatory information in a Japanese language dictionary more so than an English-English dictionary. Hence, even if searching is also performed in the English-English dictionary in practice, search results presented to the user are mostly derived from the Japanese language dictionary. Conversely, when searching is performed with an English search string, search results presented to the user are mostly derived from the English-English dictionary.
The present invention has been made to address such a technical issue, and it is an object of the present invention to provide a searching method, a searching device and a recording medium recording a computer program which are suitable for effectively presenting a search result from a plurality of document groups.